Fuzzy Comprehensive Evaluation for Urban Surface Water Pollution Risk

A comprehensive fuzzy evaluation model for water pollution risk was built according to the fuzzy mathematical method. By analyzing the average water quality values of low water season and high water season of Liaohe River drainage area Fuxin section from 1996 to 2005, the corresponding water pollution risks were carefully evaluated. The aim of this article is to quantitatively analyze and evaluate the environmental quality actualities and existing problems of the surface water in Fuxin area. The result shows that the water quality of Liao River-Fuxin section fluctuated strongly from 1996 to 2005, with an increasingly deteriorated water quality. The main pollutants of the water body were organic substances, ammonia and nitrogen, and dissolved iron. Generally, the rules of changes for various pollutants are not same. TP, BOD5 and DO had been gradually scaling up, while other pollutants in fluctuating mode.